Improvement in furnaces for making malleable iron



No. 40,710. PATENTED NGV. 24, 1863.

M. S. SALTER.

FURNAGE FOR MAKING MALLEABLE IRON.

UNITED STATESy 'PATENT OFFICE.

MOSES S. SALTER, OE SALTERSVILIJE, NEW JERSEY, ASSIGNOR TOO'HARLES H. LADD, OF PORTSMOUTH, NEW. HAMPSHIRE.

IMPROVEMENTVIN vvl-ur-:NAclas FoR MAKING MALLEABLE; IRON.

Specification forming part of Letters Patent No. 40,7 l0, dated Ndvember 24, 1863.

To @ZZ whom, it may concern:

Be it known that- I, Mosns S. SALTER, or Saltersville, in the county of Hudson and State of New Jersey, have invented certain new and useful Improvements in Furnaces for Making Iron Directly from the Ore; and I hereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, in which- `Figures 1 and 2 are sectional views of my improved furnace according t0 a vertical and horizontal plane passing, respectively, through lines a b and c d in said figure.` Fig. 3 is atop view, and Fig. 4 'a vertical section, of the same on lineA e f of Figs. 1 and 2.

My invention relates to that class of furnaces which combine in one structure several' chambers in which the various metallurgical changes ofthe iron ore duringr its process of reduction are successively effected. Those I have heretofore constructed, and for which Letters Patent of the United States were granted to me on the 20th day of November, 1849, consisted of three chambers, one above the other, all actuated by the same fire, whereof the upper chamber was used for heating and deoxidizing, the middle chamber for fluxing and working, and the lower chamber for reducing and finishing the iron. They were in some respects seriously defective. The furnaces, although presenting a desirable compactness of structure, would be liable to crack and fall to fpieces'on 'Y account of the intense heat to which the superstructure was exposed. Then the cost of apparatus and labor to hoist the material to .the-

top of the furnace to charge the same, and, finally, the working the ore from an elevated platform ina highly-heated atmosphere, were a source of great inconvenience. r

To remedy these and other defects in my furnace are the objects ofthe present invention;

and it consists, first, in combining one or more reducing-furnaces with a welding-furnace, so that the sole or hearth of either furnace shall be in the plane of or in continuity with the sole or hearth of the others; second, in the arrangement of one or niore reducing-furnaces at right angles relatively toa welding-furnace when the sole or hearth of the respective furnaces are all in the same plane; third, in the arrangement, in reducing and welding furnaces located atan angle in respect to each other, and having substantially one sole or hearth in common, of a fire-chamber in the welding-furnace and of a chimney in the reducing furnace or furnaces, so that the flame or heated gases shall pass from end to end throughout the Whole extent of the furnaces; fourth, in combining with a weldingv and one or more reducing furnaces located at an angle in respect to eachother a. single sole or hearth contracted laterally at the juncture of the reducingfurnaces with the welding-furnace; fifth, in locating the working-doors of the reducing furnace or furnaces in close vicinity of and underneath the'chimney, so that the air that may enter the furnace shall be carried off without coming in contact with the ore to be reduced; sixth, in forming an interior corner-lining of the welding-furnace by means of a cast-iron bevel tube open at both ends and extending along the border of the while the other is that of the reducing-furnaces. l

The furnaces may be built up tothe level of the sole or hearth of solid mason-work; or the hearth may be supported by pillars or a brick casing, `in which openings may be provided for yalloys/'img fresh air to sweep under the hearth,

and thus preserve the whole structure against excessive heat. The hearths of the several furnaces are situate in one andthe same plane, each forming continuation of the other.

At C is the fire-chamber. It is composed, as usual, of a grate of dre-bars overhanging an ash-pit, and is provided with an opening below the grate for the removal of the ashes, and with one above called the stock hole,7 through which the grate is supplied with fuel.v The lire-chamber is separated from the body ofthewelding-furnacebyare-brdge,D. The p present to the interior of the furnace a bevel face. Y This tube is shaped in the longitudinal sense to adapt itself to the border-line of the hearth, huggingas it were, both the hearth,

side walls, and fire-bridge all along the line h 12j k, and issuing at g and Z, where the open ends communicate with the open air.

The hearth of the welding-furnace is elongated and contracted aboutl midway, and is surmounted by a reverberatory roof depressed correspondingly with the side contraction. At this point it is intendedl to produce a white or welding heat to finally form the bloom. ',Beyoud this point the heat is tempered by increasing the capacity of the furnace. This is effected by giving that portion which is located between the reducing-furnaces and the welding-hearth proper a greater width and length, and by surmounting it with an arched roof; yet to properly concentrate the heat, (without, however, increasing its intensity,) I form bevel walls inthe corners m and a, and at the juncture of this furnace with the reducing-furnace. Upon the hearth inclosed by the bevel walls the reduced ore is worked through openings or doors at E or F, or both E and F. The object of working of thereduced ore is to expose the particles of iron to the heat of the ame, so as to bring them to a semi-Huid condition preparatory to being subjected to a White or welding heat-i. e., to such heat as will fuse and melt the earthy substances andform a liquid slag mixed in tolgether with the mass of iron.

The reducing-furnaces may be considered as continuations of the welding and working furnaces. Their hearths, side walls, and roofs are merely extensions ofthe hearth, side walls and roof of the latter. The flame and heated gases enter the reducing-furnace through the comparatively narrow passages G G', formed by the bulging side walls. H H', and the center partition-wall, I, and are consequently of a temperature less than that theyl possess in either the working or weldin g furnace. These furnaces, like theother two, have their walls built across the main angles of the structure, so as to present bevel faces toward the interior of the furnace. By this arrangement not only is the heat 'properly concentrated upon the hearth, but great strength is imparted to the structure, particularly at the angles.

At K K' are the working-doors, through which the mass of ore and coal, are occasionally stirred, to bring out all the particles alike under the'inuence and action of the heat and and springing' from the roof-.of th'e'furnace,

there is a chimney, M, firmlyestablished on the enlarged side walls as pillars.' This chimney is double or divided. by a partition-wall so arranged that each furnace has its own part or division of chimney, which, being provided with a damper, N, may perform the function of a regulator of the draft or pressure -in the furnaces. By so locating the chimney in relation to the furnaces the flame and heated gases are caused to pass from end to end through the whole extent of the furnace, andits peculiar arrangement with respect to the working-.doors enables the working of the ore without danger of fresh air coming in contact with the deoxidized or partly-deoxidized ore, as the air that may penetrate the furnace through the doors is immediately carried off up through the chimney. l

The operation of this furnace is greatly simpliied, though similar to that patented by me on the 20th day of November, 1849. y The ores,

with the materials necessary for their reduction, are thrown into the reducing-furnace through hopper-shaped receptacles in openings -in the roof. The hoppers are provided with shutters or registerfvalves, which are. closed during the intervals of filling, andthe prepared charge may be placed on the hoppers, where they undergo a semi-roasting, When/the charge in the furnaceisprocess. 4 worked off, the shutter is withdrawn andthe superincumbent charge is dropped. It is then spread kevenly over the sole of the reducingfurnace and" allowed to remain thereon, occasionally stirring it, until'the ore is reduced- 1?. e, the `oxide of iron reduced to a metallic state, The mass of iron, coal, te., is then brought into the working-furnace, where it is y frequently agitated, and when the mass comy mences to show indication offusion it is brought under the weldingarch, where,the final ball or bloom is formed, which is then squeezed and hammered inthe' usual manner.

Having thus fully described my invention and the'manner in which the same is or may be carried into effect, I will state my claims as follows:

l; The combination of one or more reducing-furnaces with a welding-furnace, so that' the sole or hearth of either'1 furnace shall be in.

the plane of or in continuity with the sole or; hearth of the others, substantially as herein: set forth. j 2. The arrangement of onevor more reducing-furnaces at right angles relatively to a welding-furnace, when the soles or hearthsof' ing furnace or furnaces in close vicinity of andl underneath the chimney, so that the air that may enter the furnace shall be carried oi without coming in contact with the ore to be reduced, substantially as herein set forth.

6. Forming an interior corner-lining of the Welding-furnace by means of acast-iron bevel tube open at both ends and extending along the border of the hearth, substantially as herein Iset forth.

In testimony whereof I have signed my name to this specification before two .subscribing witnesses.

M. S. SALTER.

Witnesses:

A. PoLLoK, WM. H. HARRISON. 

